Photo by Patrick Alexander
The U.S. Department of Agriculture Natural Resources Conservation Service (NRCS) defines ecological sites as “a distinctive kind of land with specific physical characteristics that differs from other kinds of land in its ability to produce a distinctive kind and amount of vegetation” (USDA–NRCS, 2006). Ecological sites determine not only the ecological potential of a site, but also how a site can respond to natural disturbance and management actions. Ecological sites have been delineated for many areas using physical and biotic features and are linked to soil map units. Soils, climate, hydrology, geology, physiographic features, plants species occurrences, plant community composition, annual biomass production, and plant-wildlife interactions all contribute to the proerties of ecological sites. Ecological Site Descriptions (ESDs) describe the underlying factors associated with a specific ecological site, as well as different ecological states within a given site based on factors such as grazing, fire, drought, and other management actions. For an example of an ESD, see EDIT Jornada.
Using ecological monitoring data, the overall status of an Ecological Site can be summarized into an Ecological Site Summary (ESS). At the site level, ecological site summaries generated from monitoring data can tell us about the condition and health of ecological sites based on indicators such as cover by structure and functional group, species dominance, species occurrences, canopy gap measurements, and soil stability measurements. These indicators can help inform the user of the ecological state of a given plot or overall site (i.e. shrubland state vs. grassland state). Identifying the ecological state allows us to not only determine the degree of departure from the corresponding reference ecological states, but also to inform management and restoration actions accordingly by determining the best pathway to a less degraded state. For more on state and transition models (STMs), see see Bestelmeyer et al., 2017. A major data source for developing these summaries is the Assessment, Inventory, and Monitoring (AIM) Program along with the Landscape Monitoring Framework (LMF). AIM and LMF include almost 25,000 plots throughout the western United States (see AIM Data Portal) stored in the Terrestrial AIM Database (TerrADat). Data garnered from AIM and LMF plots is both generalizable and scalable and thus applicable to management decisions across multiple disciplines at both local and national levels.
An Ecological Site Summary (ESS) tool has been developed to help users visualize the overall status of their region of interest within a specific ecological site, or across an ecological site group. This information can be summarized within a given administrative state or across political boundaries for landscape scale analysis. Ecological site summaries are generated using an R Markdown script with an interactive HTML output in which users can query summary tables, download full or filtered summary tables to view in Excel, explore interactive figures, and download static figures for their own use.
This report is an automated process and can be continually updated as new data becomes available each year or as lines of inquiry shift. This ESS information can be included in decision making processes for BLM managers, as it can help inform land use plans, grazing permit renewals, shrub or invasive species treatments, and/or seed menu development for ecological restoration and reclamation.
This report uses both boxplots and mean values with confidence intervals to summarize cover value. Boxplots can be a helpful to look at the distribution of the underlying data including the presence of outliers. Confidence intervals are a measure of variability and indicate how certain we can be of our estimates.
Intepretting a Box Plot. Modified from: https://www.wellbeingatschool.org.nz/information-sheet/understanding-and-interpreting-box-plots (accessed 22 Aug 2019)
Intertpreting Confidence Intervals
For more information on interpreting confidence intervals see the presentation from Project Leads Training 2020 PowerPoint here and presentation here.
Below is a map of all AIM and LMF plots within the Piceance-East Douglas HMA used for this report. Plots are colored by ecological site as well as year sampled.
AIM & LMF Plots Per Time Period in Piceance-East Douglas HMA
AIM & LMF Plots Per Time Period in Piceance-East Douglas HMA
AIM & LMF Plots Per Time Period in Piceance-East Douglas HMA
AIM & LMF Plots Per Time Period in Piceance-East Douglas HMA
AIM & LMF Plots Per Time Period in Piceance-East Douglas HMA
AIM & LMF Plots Per Time Period in Piceance-East Douglas HMA
AIM & LMF Plots Per Time Period in Piceance-East Douglas HMA
AIM & LMF Plots Per Time Period in Piceance-East Douglas HMA
AIM & LMF Plots Per Time Period in Piceance-East Douglas HMA
AIM & LMF Plots Per Time Period in Piceance-East Douglas HMA
AIM & LMF Plots Per Time Period in Piceance-East Douglas HMA
AIM & LMF Plots Per Year in Piceance-East Douglas HMA
Percent cover summaries use data from Line-point intercept (LPI) method to determine average cover of individual species, as well as summaries by structure and functional group cover and noxious versus non-noxious cover. More information on the LPI protocol can be found in the Monitoring Manual for Grassland, Shrubland, and Savanna Ecosystems. From the AIM data, we can make some simple figures showing cover values. These figures, along with the summary tables, can quickly be incorporated into any documents where this data is used (i.e. NEPA documents for grazing permit renewals, shrub treatments, etc). For more information on AIM data, including how indicators are calculated, BLM users can access the TerrADat metadata here.
The boxplot cover summaries are generated from species indicator data and therefore may be an overestimation of cover for functional group as it does not take into account
Short Stature Perennial Grasses status was determined by Sage Grouse biologists and modified slightly in each state. The full list can be found in tblStateSpecies in the SG_Group field where SG_Group field is ‘TallStaturePerennialGrass’ and the StateSpecies field has the two letter state code for the desired state (e.g. ‘CO’).
These include: POSE, BOGR2, ARPU9, MUTO2, ACPI2, ACWE3, AGHU, AGVA, BLTR, FEBR, FEEA3, FESA, MUFI,PIEX4, POCU3, POJU, PONEI2, POSA12, POSC and VUOC.
Tall Stature Perennial Grasses status was determined by Sage Grouse biologist and modified slightly in each state. The full list can be found in tblStateSpecies in the SG_Group field where SG_Group field is ‘TallStaturePerennialGrass’ and the StateSpecies field has the two letter state code for the desired state (e.g. ‘CO’).
These inlcude: ACHY, AGCR, BRIN2, ELEL5, FEID, HECO26, KOMA, PASM, PLJA, PSSP6, SPAI, SPCR, THIN6 etc.
Foliar cover values are summarized in tables below. Tables summarize data across the ecological site as well as by plot within the ecological site. Note that percent cover on a per-plot basis is not cumulative because we are calculating cover from any hit on line point intercept. Percent cover values per plot could therefore potentially add up to over 100. See Ground Cover Summary Table for total foliar cover estimates. Per plot measurements are intended to allow you to compare plot level data to the status of the ecological site as a whole.
Percent cover by species by plot within your study area.
Percent cover by species averaged across the study area by ecological site.
Average percent cover by structure and functional group across your study area.
Average percent cover by structure and functional group across your study area.
Percent cover by noxious versus non-noxious plants by plot within your atudy area.
Percent cover by noxious versus non-noxious plants averaged across your study area.
Percent cover by woody versus herbaceous plants averaged across your study area.
It is unlikely that all species on a plot will be detected in line point intercept. It can be inferred that these species that were never detected in LPI have “low abundance” across this ecological site. To determine all species detected on plots throughout an ecological site (or other grouping feature), we can pull in all species detected from all other methods using the accumulated species indicator. This can give us an idea of overall diversity across the ecological site, indicate seed bank and restoration potential, and inform us more about community composition and species trends as plots are repeatedly surveyed.
This table contains species that were only ever detected in species richness inventory on a per plot basis within the study area.
This table contains species that were only ever detected in species richness inventory across the entire ecological site.
In addition to species-specific indicators, we can summarize ground cover indicators to get percent cover values for bare ground, total rock, total litter, and total foliar. Additional indicators that can be included here are Lichen (“LC”) , Moss (“M”) , Duff (“D”), and/or Cyanobacteria (“CY”). These calculations are informative for assessing the status of the ecological site as a whole, susceptibility to erosion, and/or cross-walking AIM data to Rangeland Health Assessments when used in conjunction with species specific calculations.
##
Ground cover indicator values by plot within the specified ecological site.
Ground cover values averaged across the specified ecological site.
Canopy gap intercept can inform us about potential wind erosion, weed invasion, and wildlife habitat. When combined with vegetation height measurements, gap measurements can inform us about vegetation structure (see p. 41 in the Monitoring Manual for methods). Canopy gap, bare soil, and vegetation heights c an also be used to determine thresholds at which vegetation structure may lead to a shift in ecological states.
##
The table below shows gap size classes represented within each plot within the specified ecological site.
Below is a summary of average percent cover within each gap size class across the specified ecological site.
Soil stability provides information on soil structure development and resistance to erosion. The soil stability test measures the soil’s stability when exposed to rapid wetting, and reflects soil biotic integrity (see page 47 in the Monitoring Manual.)
Below are the soil stability ratings for each individual plot within the specified ecological site.
Below are the average soil stability ratings within the specified ecological site.
Remotely sensed estimates from the RAP tool
Mean indicator values from 2011-2015 and 2016-2020 were compared using t-tests and Mann Whitney-U tests. These tests assume
Rows with lower p-values can help you focus on the differences which are strongest. Comparisons with a p-value of 0.2 or lower are significant at the 80% Confidence level. Blank p-values indicate rows where statistical comparisons were unable to be made due to sample size limitations.